We had a script reading, and that's where we met J.K. Rowling, which was really exciting.
— Rupert Grint

Three children have become adults since a phone call with Jo rowling, containing one small clue, persuaded me that there was more to Snape than an unchanging costume, and that even though only three of the books were out at that time, she held the entire massive but delicate narrative in the surest of hands.
Alan Rickman rowling quote

J.K. Rowling said Bellatrix's role was going to be significant in the last one, when I showed some reluctance in playing a tiny bit part. Up front, they said, 'You're very significant in the last one.' But significant could mean a lot of things. That could just mean a significant plot point. Doesn't necessarily equal big part.
— Helena Bonham Carter

People always tell me I'm nothing like my character. Well, hopefully not! He's a character who's very defined. He was purposefully written by Jo Rowling as very one-dimensional in the first few books, because you're supposed to hate him.
— Tom Felton

Well just meeting J. K. Rowling was amazing because she created all this world. And all the fans, we all get so obsessed with it and then you met the one person who made it all up. It was just so amazing. And I was just so amazed that that she wrote this book and all of the films have happened.
— rowling quotation by Evanna Lynch